Multipaint is a new, open-source, cross-platform pixel graphics editor, created by Tero Heikkinen aka DrTerrorZ. Inspired by Deluxe Paint from Amiga, Multipaint targets the ZX Spectrum, MSX-1, and C64 home computers. On the latter, both hi-res and multi-color modes are suppored.
Multipaint is written in Java and should run on all major OSes with a Java Runtime installed. More details, downloads, and the source code can be found on the project website.